Trolley hoist



Juge 24, 1930. c, oc ET A "1,767,467

TROLLEY H01 5 1' Filed Sept. 15. 1926 2 Sheets-Sheet l ATTORNEYJ June 24, 1930.

c. H. LQCH'ER ET AL TROLLEY HOIS '1 Sheets-Sheet 2 Filed Sept. 15, 1926 A TTORNEYJ Patented June 24, 1930 UNITED STATES PATENT creme CHARLES H. LOCKER, 0F HANCOCK, MARYLAND, AND JOHN P BURT, 0F KEARNY,

NEW JERSEY; SAID BURT ASSIGNOR TO HARNISCHFEGER CORPORATION, OF MIL- WAUKEE, WISCONSIN, A CORPORATION OF WISCONSIN TnoLLEY nors'r Application filed September 1926. Serial No. 135,517.

a controller, a cable drum and a train of reduction gears connecting-the drumto the motor for operation thereby, suitable manually-operable control levers being provided whereby thedrums may be operated inde-i pendently of each other.

In using certain types of buckets, as for example skip buckets in a trolley hoist, a

slight dilference in the rate of operation'of the motors in hoisting causes pulling in on one cable or hne at a greater rate than on the other thus tilting the bucket and oftentimes dumping part of the load prematurely,

thereby endangering the lives of workmen below. Another difiiculty encountered in using a skip bucket in a grab bucket hoist is that there is an objectionable side sway to the skip so that when the latter is run within the narrow confines of the trolley supporting bridge or structure it has a tendency to sway sideways and strike one of the structural members, thus causing itto dump part of its load. I, v

One of the obj ectsof the present invention,

therefore, is to provide, in a. trolley hoistof.

the character referred to, improved means for controlling the motorswhereby the same may be operated simultaneously at thesame rate to adapt the hoist for skip bucket work."

Another objectis to provide, in hoist.

of the character referred to, improved means for suspending or supportlng a skip bucket therefrom whereby side-swaying 'of" the" bucket is eliminated to a large extent.

Another object is to provide anflmproved hoist of the character, referred to for operating a skip bucket, and which is readily 6011-. trolled to preventpremature dumping or tiltingmovement of the bucket, and further to provide apparatus of thecliaracter described wherein the bucketmay be moved through a diagrammatic, some of the parts 'being removed for, the sake of clearness;

Fig; 2 is an elevational View looking towards the left in Fig. 1, some of the parts being removed forthe sake of clearness;

Fig. 3 is an end elevational view ofthe control mechanism for the motors and Fig. 4: is an elevational view partly in sec tion and looking towards the left in 3, tfhe section being taken on the line 44.in

*ig. 3. v 2

The trolleyhoi'st isshown diagrammat ically in Fig. 1 as comprising the t'wo'separate units. which are mounted for movement together along an overhead track or bridge (not shown) of well known construction, one unit comprising the holding drum 10, the operating motor 11 therefor,'and the train of gears 12,13, 14 and 15 connecting the drum to the motor-for operation thereby, the other unit comprising the'tripping drum 16,the operating motor 17 and the: train of gears 18,19, 20 and21 connecting the drum to the motor for operation thereby. j

The pair ofcables 22 and 23 are fixed at their upper ends to drum 10 for Winding thereon as more clearly shown in Fig. '2, and are trained about sheaves 24 and 25 journale'd respectively in frames 26 and 27 carried by and spaced along the bail 28 from which the skip bucket 29 is suspendedby the chains 30, 31 and 32, Thechains 30 and 31' are secured at their upper ends to the ends of bail 28 means of brackets 33 and are, se-

cured at theirlower ends to the rings 34 secured to the sides .of 'the bucketfforwardlv of the center of gravity thereof. The chain 32 is connected at one end to the bail 28 at a point intermediate the endsjof the latter and at itsother end tothe ring 35secur'ed manner. Any inequalities of the parts between levers 44 and 45 and the controller contacts may be compensated for by adjusting plates 49 and 50.

The levers are in their neutralposition when vertical and operate the motors in the hoisting direction upon movement to the right, as viewed in Fig. 3, and reverse the motors to lower the bucket when moved to the left of their neutral position, Starting with the levers in their neutral position as 4 shown in Figs. 3 and 4, therefore, with the latches 53'and 54 in notches 51 and 52 to lock the. levers against relative pivotalmovement with respect to each other about the axis of shaft 41, movement of the levers to the right of the neutral position causes simultaneous starting and operation of the motors 11 and 17 at the same rate to lift the bucket. During the lifting of the bucket, the lever 46 may beactuated to operate the usual motor (not reached, the operator releases or raises latch.

53 and moves lever 44backto neutral position, thus stopping motor 11. Continued operation of the motor 17 then causes movement or the bucket to dumping position in the manner explained above, after which lever 45 is moved to its extreme position to the left to reverse motor 17, latch 54 remaining in notch whereby the quadrants 48 and 47 are carried around together with lever 45. When motor 17 has reversed sufficiently to cause return movement of bucket 29 to the. full line position shown, lever 44 is also moved to the left until latch 53 drops into notch 51 iuuler the action of spring 55, at which time the motors 11 and 17 operate synchronously at the same rate and the bucket lowered, lever 46 having been subsequently reversed to return the trolley'hoistto its starting point. When the bucket has been lowered to the proper point, both levers 44 and 45 are returned to their neutral positions and the motors 11 and, 17 are thereby stopped. If, for any reason, there is a greater pull on one of the cables 22 and 23 than on the other, the bar :3? wi l tilt slightly in the plane of the paper, as viewed in'lfig, 2, thus compensating for any unevenness and preventing side sway of the bucket which would otherwise occur if the ends of the cables 22 and 23 were deadended on the bucket or its associated parts;

It will therefore be seen that improved control mechanism has been provided for a trolley hoist of the character referred to whereby a skip bucket may be used with the same efiiciency and effect as'a grab bucket,"

and that the skip bucket is held against undue side swaying-and premature dumping, and

may be moved at full speedthroughits cycle of operation tocdumping position and return. Y 1

One embodiment of the invention has been shown and described, but of course various changes may be made, such as in the size, shape and arrangement of parts without departing from the spirit of the invention-or the scope of the claims, I V

The invention claimed is:

1. The combination with hoisting appara-' tusof the character described including cable drums and driving motors therefonof manually-operable control levers for said motors, a shaft for supporting said levers for movement independently ofeach other, said levers beingoperable upon movement into agiven relationwith respect to each other to cause equal effective hoisting and lowering,

movement of said drums, and means cooperable, with said levers for locking the sameto the shaft in such relation.

2. A control mechanism for the driving motors of the cable drums of hoisting apparatus comprising a shaft, nanually-operable control levers for said motors loosely mounted on said shaft for. pivotal movement about the axis thereof and operable when in a given angular relationwith respect to each other to cause equal effective hoisting and lowering movements of vsaid drums, and means fixedon said shaft for coaction with said levers to hold the latter in said relation with respect,

to each other. for pivotal controlling movement about said axis. I

3. A control mechanism for the driving motors of the cable drumsof hoisting apparatus comprising a shaft, manually-operable control levers for said motors loosely-mount-.

ed on said shaft for pivotal movement about the axis thereof and operablewhen in a given angularrelation with respect to each other to cause equal effective hoisting. and lowering movements of said drums, means operable to locksaid levers in said relation anifl comprising latches carried by said levers, quadrants fixed OII'SEHCl shaft and provided with notches arranged to receive said latches when said levers are in said relation, and

means for withdrawing said latches-from said notches. i

4. In hoisting apparatus of thecharacter described,a bail, a skip bucket suspended therefrom, apairof sheaves carried'by said bail and spaced along the same, a pair of drums, a rigid-bar, a pair' ofcables trained about said sheaves and secured at their re spective ends to one of saiddrums and to the ends of Sfil'ClbtI, a thirdcable secured at one end to the other of said'drums and at its other end to said bar at a point intermediate 1 the ends ofthe latter, means for operating said drums independently of each other,

1 and meansoperable upon operation of said drums in such wise as to haul in on'the third cable at a greater rate than on said pair of cables to tilt said bucket to dumping position, said last-named means comprising a flexible element connected at one end to said bar and at its other end to the rear end of said bucket.

5. A hoisting apparatus of the character described, comprising a pair of drums, a pair of cables connected to one drum, another cable connected to the other drum, an equalizer interconnecting the cables, a skip bucket sus pended on the pair of cables, a flexible con nection between the skip bucket and the other cable operating when tensioned to tip the skip bucket and dump the contents thereof, and means for-selectively operating said drums simultaneously or independently whereby when said drums are simultaneously operated, the bucket may be raised and lowered Without tipping and when one of said drums is operated while the otherremains stationary, the flexible connection may be tensioned to discharge the contents of the bucket.

6. A hoisting apparatus of the character described, comprising a pair of drums, a pair of cables connected to one of said drums, an equalizer bar connected to said pair of cables, a cable connected to the other drum and to the equalizer bar intermediate the ends thereof, an arrangement of sheaves suspended on said pair of cables, a skip bucket carried by said sheaves, and means for operating said drums.

'TpA hoisting-apparatus of the character described, comp isin a pair of drums, cables connected to the drums, means for interconnecting the cables, a skip bucket, means for suspending the skip bucket on a pair of the cables connected to one of the drums, indi- Vidual motors for driving the drums, manually operable control levers for said motors supported for movement independently of each other and also operable upon movement in a certain relation with respect to each other to cause equal efiective hoisting and lowering movements of said drums, releasable means operable to interconnect and lock said levers in said certain relation, hand grips mounted on the levers, and controlling the operation of said releasable means, and means controlled by said other cable and cooperating with the bucket for tipping the bucket to discharge the contents thereof when one of the drums is operated while the other remains stationary. i

In witness whereof, we hereto'a 1 our signatures.

CHARLES H. LGCHER. JOHN P. BURT. 

